package demo;
import pojo.*;
public class Text {
    public static void main(String[] args) {
        Father b=new Son1();
        Son2 c=new Son2();
        Son1 d=new Son1();
        b.a();
        d.a();
        c.a();
        System.out.println(b instanceof Father);
        System.out.println(b instanceof Son2);
    }
}
